Unit tests: number fields

[lealobanov]

Description

Adds unit tests for: com.nftco.flow.sdk.cadence.UFix64NumberField; com.nftco.flow.sdk.cadence.UInt64NumberField; com.nftco.flow.sdk.cadence.UInt8NumberField; com.nftco.flow.sdk.cadence.NumberField;

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For contributor use:

• [x] Targeted PR against master branch
• [x] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• [x] Code follows the standards mentioned here.
• [x] Updated relevant documentation
• [x] Re-reviewed Files changed in the Github PR explorer
• [x] Added appropriate labels

[github-actions[bot]]

Unit Test Results

  19 files  ±0    19 suites  ±0   27s :stopwatch: ±0s 115 tests ±0  115 :heavy_check_mark: ±0  0 :zzz: ±0  0 :x: ±0 

Results for commit 65cf8ac5. ± Comparison against base commit 65cf8ac5.

:recycle: This comment has been updated with latest results.